Apparatus for mass production of metal substrates used in purification of exhaust gas and the method of producing metal substrates using the same

ABSTRACT

The present invention relates to an apparatus for mass production of metal substrates used in catalytic purification of exhaust gas, which comprises: (a) an uncoiler part for continuously feeding a strip in the lengthwise direction, wherein said strip is coiled along the rotation axis; (b) a tubing processing part for changing the strip into the shape of a pipe by means of gradually putting pressure through multi-stage rolls onto the both side edges of the strip in feed from said uncoiler part; (c) a feeder part, which is installed at one side of said tubing processing part, for feeding a pre-made honeycomb body at an equal interval to the strip being changed into the shape of a pipe; (d) a welding part, which is installed at the rear end of said tubing processing part, for welding into a unit the both side edges of the strip in feed after being changed into the shape of a pipe; (e) a sizing part, which is installed at the rear end of said welding part, for evening the girth of the pipe in feed; and (f) a cutting part for cutting the pipe in feed from said sizing part into equal intervals.

FIELD OF THE INVENTION

[0001] The present invention, which is used in catalytic purification of exhaust gas of an internal combustion engine, relates to an apparatus for mass production of metal substrates and the method of producing metal substrates using the same by means of continuously inserting pre-made honeycomb bodies into the metal outer shells.

BACKGROUND OF THE INVENTION

[0002] With respect to the terms used in the specification, a “honeycomb body” refers to a thin metal sheet rolled into the shape of a honeycomb, and an “outer shell” refers to a metal pipe for inserting said honeycomb body. A “metal substrate” refers to a product in which said honeycomb body has been inserted into the outer shell.

[0003] The methods of inserting a honeycomb body into a metal outer shell can be classified into two main types. First, it is a method of inserting a honeycomb body into a pre-joined outer shell in the shape of a pipe. Japanese Patent No. 5-228376, 6-390, 6-391, 6-47284, 6-63421, 6-182222, 6-238174, 7-24330, 8-206512; U.S. Pat. No. 5,366,700. Second, it is a method of inserting a honeycomb body into a non-joined outer shell in the shape of a “C” or into an outer shell of several pieces cut lengthwise, followed later by joining of the outer shell. Japanese Patent No. 4-122418, 5-220404, 6-269683, 6-277527; U.S. Pat. No. 5,316,997.

[0004] These methods are appropriate for small lot production of products of various shapes and sizes. However, while mass production of a single product is characteristical of the manufacturing industries such as automobiles and motorcycles, these methods are not appropriate for mass production as such. In particular, for the purpose of making an outer shell, during the process of cutting the sheet into several pieces and changing the same into the shape of a pipe, there is no structural part to secure them in a precise position, which in turn leads to a slight movement therein. Consequently, while in the shape of a pipe as transformed, at the time of welding the both side edges into a unit, the welding machine may not precisely align with the welding area, which in turn becomes a cause of defective products.

[0005] Further, an additional sizing process is necessary to shape the pipe into a complete cylinder after welding by evening the girth of the pipe, or to shape it into a track shape, if needed, by compress-molding the cylindrical pipe into the track shape. In the case of sizing as such, it is carried out while supporting the pipe cut into a piece, but at the time of sizing, the pipe can move slightly, which leads to a problem of imprecise sizing.

SUMMARY OF THE INVENTION

[0006] The objective of the present invention lies in providing an apparatus for mass production of metal substrates used in purification of exhaust gas, and the method of producing metal substrates using the same, which renders the transformed pipes immovable for accurate welding at the welding area in addition to efficiently carrying out the sizing operation.

[0007] Another objective of the present invention lies in providing an apparatus for mass production of metal substrates used in purification of exhaust gas, and the method of producing metal substrates using the same, which integrates the following processes into one process for simplifying the multi-step manufacturing process of the prior art: tubing process of an outer shell into the shape of a pipe, inserting process of a honeycomb, and welding process of an outer shell.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0008] In order to achieve said objectives, the apparatus for mass production of metal substrates used in purification of exhaust gas, according to the present invention, in its basic technical concept, comprises as follows: (a) an uncoiler part for continuously feeding a strip in the lengthwise direction, wherein said strip is coiled along the rotation axis; (b) a tubing processing part for changing the strip into the shape of a pipe by means of gradually putting pressure through multi-stage rolls onto the both side edges of the strip in feed from said uncoiler part; (c) a feeder part, which is installed at one side of said tubing processing part, for feeding a pre-made honeycomb body at an equal interval to the strip being changed into the shape of a pipe; (d) a welding part, which is installed at the rear end of said tubing processing part, for welding into a unit the both side edges of the strip in feed after being changed into the shape of a pipe; (e) a sizing part, which is installed at the rear end of said welding part, for evening the girth of the pipe in feed; and (f) a cutting part for cutting the pipe in feed from said sizing part into equal intervals.

[0009] Below, the present invention is described in detail through an embodiment in its representation, which in turn is illustrated in the attached figures.

[0010] As shown in FIG. 1, which illustrates the embodiment herein, the present invention comprises as follows in its implementation of its basic technical concept: (a) an uncoiler part 10 for continuously feeding a strip 1 in the lengthwise direction, wherein said strip is coiled along the rotation axis 11; (b) a tubing processing part 20 for changing the strip into the shape of a pipe by means of gradually putting pressure through multi-stage rolls 21 onto the both side edges of the strip 1 in feed from said uncoiler part 10; (c) a feeder part 30, which is installed at one side of said tubing processing part 20, for feeding a pre-made honeycomb body 2 at an equal interval to the strip 1 being changed into the shape of a pipe; (d) a welding part 40, which is installed at the rear end of said tubing processing part 20, for welding into a unit the both side edges of the strip 1 in feed after being changed into the shape of a pipe; (e) a sizing part 50, which is installed at the rear end of said welding part 40, for evening the girth of the pipe 1 a in feed; and (f) a cutting part 60 for cutting the pipe 1 a in feed from said sizing part 50 into equal intervals.

[0011] Here, the strip 1 refers to a strip while in feed from the uncoiler part 10, prior to its welding, and the pipe 1 a refers to a welded strip after being changed into the shape of a cylinder.

[0012] Prior art involves first cutting the strip 1 into several pieces to form them respectively into the shape of a pipe, followed by welding and sizing. Unlike the prior art, however, the present invention is structured in such a way to continuously feed the strip 1 in the lengthwise direction, while being supported, followed later by cutting. As such, there is no movement whatsoever on the part of the strip 1. Consequently, the present invention leads to quality improvement due to its precision operations in terms of molding, welding and sizing of the strip.

[0013] Furthermore, the present invention enables mass production of metal substrates by operating an integrated automatic system of the following processes: tubing process of an outer shell into the shape of a pipe, inserting process of a honeycomb, welding process of an outer shell, and cutting process of a pipe.

[0014] The method of producing metal substrates by means of an apparatus according to the present invention as above comprises the following steps of: (a) forming a strip 1 to change it into the shape of a pipe in the lengthwise direction by putting pressure on the both side edges thereof while in feed; (b) inserting a honeycomb body 2 into said strip 1 at an equal interval, wherein said honeycomb body 2 is pre-made during the step of forming the strip 1 into the shape of a pipe; (c) welding the both side edges of the pipe inserted with said honeycomb body 2; (d) sizing the pipe by evening said welded pipe; and (e) in completion, cutting the pipe 1 a at a desirable interval after undergoing said step of sizing.

[0015] Here, in the step of inserting a honeycomb body, it is preferable to insert a dummy bar 3, which is concave at the center, between the honeycomb bodies 2. It is preferable to have a dummy bar that is concave at the center in the shape of a spool. This type of design results in reusability since the dummy bar, as shown in FIG. 4, does not become damaged at the cutting area on the pipe 1 a when the pipe is cut.

[0016] In examination in further detail of the structural elements of the present invention as above, the uncoiler part 10, as shown in FIG. 1, is a structural part which continuously feeds the strip 1 in the lengthwise direction, wherein said strip is coiled at the rotation axis 11. The structure is in place to support the cut metal strip 1 and continuously feed the same thereto according to the diameter of the outer shell. By continuously feeding the strip 1 in the direction of progression while being supported at the multi-stage rolls 21, the strip 1 is thus rendered immovable.

[0017] The tubing processing part 20, as shown in FIG. 1, has a number of multi-stage rolls 21 in place, each of which has a smaller sectional area towards its concave center. The tubing processing part 20 carries out the role of changing the strip into the shape of a pipe by gradually putting pressure onto the both side edges of the strip 1 in feed from the uncoiler part 10. In particular, at the center, at the one side of the tubing processing part 20, it is connected to the supply part 30 so that a honeycomb body 2 can be inserted therein before the width of the upper portion of the part to be welded on the C-shaped strip 1 becomes lesser than the outer diameter of the honeycomb 2.

[0018] The feeder part 30, as illustrated in FIG. 1 through FIG. 3, is a structural part, installed at one side of the tubing processing part 20, which feeds a pre-made honeycomb 2 to the strip 1 at an equal interval while said strip 1 is being changed into the shape of a pipe. The feeder part 30, which is situated vertically above the upper portion of the tubing processing part 20 or the area to be welded, carries out the role of feeding the pre-made honeycomb 2 at a pace in line with the speed of progression of the strip 1 during the tubing process by using such a means of feed as a conveyor belt 31. At that time, as described above, it is preferable to feed a dummy bar 3 between the honeycomb bodies 2 in order to maintain a certain interval in between.

[0019] The welding part 40, as shown in FIG. 1, is a structural part, installed at the rear end of the tubing processing part 20, for welding the strip 1 into a unit with a welding implement 41 while completely joining the both side edges of the strip 1 with the holders 42 for leveling the welding area, wherein said strip is in feed after being changed into the shape of a pipe. The welding part 40 is designed in such a way to allow continuous welding of the joined areas on the pipes as the area to be welded on the strip is moved forward from the tubing processing part 20 after the completion of forming it into the shape of a cylinder via multi-stage rolls 21. At that time, a welding implement 41 such as an ordinary oxygen-gas, TIG, MIG, or laser welding machine can be used. Since the immovable strip 1, as supported, is fed to the welding area 4, it thereby allows accurate welding on the pipe 1 a.

[0020] The sizing part 50, as shown in FIG. 1, installed at the rear end of the welding part 40, is a structural part for evening the girth of the pipe 1 a with the sizing rolls 51. It is used to make the shape of a pipe completely cylindrical after being welded completely in the welding part. In the sizing part 50 as well, since the immovable strip 1, as supported, is fed thereto, the sizing of a pipe 1 a can be thereby carried out with precision.

[0021] The cutting part 60, as shown in FIGS. 4 and 5, is a structural part for cutting the pipe 1 a in feed from the sizing part 50 at an equivalent interval. The cutting part 50 comprises (a) rails for allowing movement 61, having a pair of stoppers 61 a for respectively limiting the traveling distance thereof back and forth, wherein said rails are installed side by side at the lower part of said cutting part 60 along the direction of the pipe in feed; (b) a frame body 62 in the shape of a box, which allows passage of said pipe 1 a through the interior thereof, the lower part of which has wheels for moving back and forth to the extent of stoppers 61 a along the rails 61; and (c) cutting wheels 63, which are supported within said frame body 62, for cutting the pipe passing through the interior of the frame body.

[0022] Here, the frame body 62, as shown in FIG. 4, moves forward by force of progression of the pipe 1 a and returns to its original position by means of a return spring 62 b. At that time, the force of a return spring 62 b should be less than the force on the frame body 62 moving forward.

[0023] Further, as shown in FIG. 5, the cutting wheels 63, which are made 180° rotatable, are installed as a pair, facing each other, on the both sides within the frame body 62. The cutting wheels 63 are supported by a wheel-support piece 63 a, which in turn is connected to a support rack 63 a by a crank 63 b.

[0024] The cutting part 60 as above cuts the pipe according to the set length, at the position of a dummy bar 3 as inserted between the honeycomb bodies 2. In particular, for the purpose of reusing the dummy bars, the cutting wheels 63, as they revolve around the girth of the pipe 1 a, cut only the outer pipe. For the purpose of continuously feeding the strip, the cutting part 60 is designed to move back and forth on the rails for allowing movement 61 as between the stoppers 61 a. As the pipe is advanced forward, the cutting is effectively carried out therein. Moreover, for the purpose of cutting at an accurate length, a controller, which can control the timing and the length, can be installed thereto.

[0025] Meanwhile, in the case of using a pipe, cut lengthwise, with a cross-section in the shape of a “C” by way of undergoing a primary tubing process, an uncoiler part 10 and a tubing processing part 20 can be omitted therein. In such a case, a tightening part is needed to tighten the area to be welded on the pipe in addition to a feeder part, which is designed to insert a number of honeycomb bodies therein.

[0026] As shown above, the apparatus for mass production of metal substrates and the method of producing metal substrates using the same according to the present invention in effect carries out accurate welding and sizing operations due to the fact that the strip is made not to break away from the precisely set position set by way of continuously feeding the coiled strip while supporting it through multi-stage rolls.

[0027] Further, the present invention has the effect of substantially reducing manufacturing time along with cutting unit cost since it enables mass production of products of certain specifications by way of its simple process as compared to that of the prior art.

[0028] Moreover, the present invention allows insertion of a honeycomb body without damage into the outer shell. It also allows close contact between the honeycomb body and the outer shell, which in turn enhances durability and permeability of the product. Moreover, the present invention has the effect of reducing installment cost of the apparatus since it uses a TIG or MIG welding machine, which is comparatively cheaper than the laser-welding machine. 

What is claimed is:
 1. An apparatus for mass production of metal substrates used in purification of exhaust gas, which comprises: (a) an uncoiler part for continuously feeding a strip in the lengthwise direction, wherein said strip is coiled along the rotation axis; (b) a tubing processing part for changing the strip into the shape of a pipe by means of gradually putting pressure through multi-stage rolls onto the both side edges of the strip in feed from said uncoiler part; (c) a feeder part, which is installed at one side of said tubing processing part, for feeding a pre-made honeycomb body at an equal interval to the strip being changed into the shape of a pipe; (d) a welding part, which is installed at the rear end of said tubing processing part, for welding into a unit the both side edges of the strip in feed after being changed into the shape of a pipe; (e) a sizing part, which is installed at the rear end of said welding part, for evening the girth of the pipe in feed; and (f) a cutting part for cutting the pipe in feed from said sizing part into equal intervals.
 2. The apparatus for mass production of metal substrates used in purification of exhaust gas according to claim 1, wherein said cutting part comprises: (a) rails for allowing movement, having a pair of stoppers for respectively limiting the traveling distance thereof back and forth, wherein said rails are installed side by side at the lower part of said cutting part along the direction of the pipe in feed; (b) a frame body in the shape of a box, which allows passage of said pipe through the interior thereof, the lower part of which has wheels for moving back and forth to the extent of stoppers along the rails; and (c) cutting wheels, which are supported within said frame body, for cutting the pipe passing through the interior of the frame body.
 3. A method of producing metal substrates used in purification of exhaust gas, wherein said method comprises the steps of: (a) forming a strip to change it into the shape of a pipe in the lengthwise direction by putting pressure on the both side edges thereof while in feed; (b) inserting a honeycomb body into said strip at an equal interval, wherein said honeycomb body is pre-made during the step of forming the strip into the shape of a pipe (c) welding the both side edges of the pipe inserted with said honeycomb body; (d) sizing the pipe by evening said welded pipe; and (e) cutting the pipe at a desirable interval after undergoing said step of sizing.
 4. The method of producing metal substrates used in purification of exhaust gas according to claim 3, wherein said step of inserting a honeycomb body comprises inserting a dummy bar, which is concave at the center, between the honeycomb bodies. 